Machines, such as excavating machines, material handling machines, vehicles, and generators, generally include various components and/or systems that require a fluid for proper operation. The type of fluid may vary with the particular component or system. For example, engines, such as gasoline engines, diesel engines, and gaseous-fuel powered engines, may require a lubricating fluid such as engine oil. Typically, engine oil or other system fluids and lubricants may be circulated within an associated component or system by a pump, such as a gear pump.
Engine oil or other system fluids may be exposed to wide variations in temperature including high heat, for example from engine operation. During machine operation, lubricating fluids may become contaminated by various substances, such as metallic particles from mechanical wear or the addition to the fluid of an incorrect additive package. In addition, engine oil may experience acid buildup, breakdown, and/or shearing of molecules and suffer a loss of optimum lubricating properties. All of these factors may lead to failure of a lubricating or other fluid to optimally achieve its primary purpose, such as lubricating and extending the life of machine components and systems. As a result, increased maintenance time and costs and even machine system failure may result.
Lubricating fluids such as engine oil may be monitored manually via a so-called dip stick. Other machine fluids may be checked by visual inspection. This may allow, in addition to determination of the level of fluid present, a rough determination of contamination. A more accurate determination may be made by taking a sample for external analysis of the level and type of contaminants or the degree of breakdown of fluid properties. In addition, some systems may include sensors capable of sensing certain contaminants in a fluid.
The use of manual determination of the quality of fluids relies on a technician or machine operator making what may at best be a rough guess. Taking samples for laboratory analysis may be unduly time consuming and still may rely on employees scheduling the sampling process. Where an incorrect additive package has been introduced, damage may already have been done by the time a sample has been taken. Currently available sensors may give only a partial analysis for a certain contaminant. It would be both beneficial and desirable to be able to remotely monitor a range of contaminants and/or characteristics of fluids, such as engine oil, hydraulic fluid, etc., to obtain continuous or closely intermittent data on the quality of the fluid.
One fluid sensing system is disclosed in U.S. Patent Application Publication No. 2014/0188404 naming Von Herzen et al. as inventors and published on Jul. 3, 2014 (“the '404 publication”). Specifically, the '404 publication discloses a fluid sensing system including multiple sensors submerged in the fluid to be monitored. An exemplary embodiment disclosed in the '404 publication includes multiple sensing components mounted on a bolt, which may be the bolt typically employed as a drain plug in an oil pan.
While the system disclosed in the '404 publication may be suitable for monitoring the character of fluids, it may be unduly complex and too expensive for general use. The system includes a number of sensitive components which must endure high temperature while continuing to function accurately. Furthermore, the system of the '404 publication may not be suitable for the harsh environment and operating conditions experienced by heavy equipment such as excavators and mining machines.
The disclosed system for monitoring machine fluids is directed to overcoming one or more of the problems set forth above.